Lung Cancer in Chrysotile Asbestos Workers: Analyses Based on the Two-Stage Clonal Expansion Model

Details

• Personal Author:
  Richardson DB
• Description:
  OBJECTIVE: To evaluate the magnitude and temporal pattern of lung cancer risk following exposure to chrysotile asbestos. METHODS: I analyzed data on lung cancer mortality in a cohort of asbestos textile workers who were exposed to almost pure chrysotile. Employment history and industrial hygiene data were used to derive asbestos exposure estimates. These data were analyzed within the framework of the two-stage clonal expansion (TSCE) model and the Cox proportional hazards model. RESULTS: Under the TSCE model, the association between chrysotile asbestos and lung cancer mortality was primarily due to an exposure-induced increase in the proliferation of initiated cells. In a setting of protracted exposure to chrysotile asbestos, this model implies that the estimated hazard ratio was at its maximum between ages 40 and 65 years. Cox regression analyses support these conclusions; the estimated excess relative risk per fiber-year/ml was 0.053 (95% CI: 0.023, 0.124) at ages <65 years, while there was minimal evidence of association at older attained ages. CONCLUSIONS: The TSCE model fits these data well, accommodating the observed departure from the proportional hazards assumption. These analyses suggest that the effect of chrysotile asbestos exposure on lung cancer risk varies with attained age. [Description provided by NIOSH]
• Subjects:
  Age Factors Aging Benzene Environmental Monitoring Lung Lung Diseases Mortality Neoplasms Occupational Diseases Occupational Exposure Occupational Health Respiratory System Respiratory Tract Diseases Risk Assessment Safety

  More +
• Keywords:
  Age-factors Age-groups Author Keywords: Asbestos Benzenes Cancer Cancer-rates Cell-biology Cell-metabolism Cell-morphology Cellular-reactions Cohort Study Exposure-assessment Exposure-levels Exposure-methods Lung Cancer Mathematical-models Models Mortality-data Mortality-rates Occupational-diseases Occupational-exposure Occupational-hazards Pulmonary-cancer Pulmonary-disorders Pulmonary-system-disorders Risk-analysis South Carolina Statistical-analysis

  More +
• ISSN:
  0957-5243
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  North Carolina ; OSHA Region 4
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  20
• Issue:
  6
• NIOSHTIC Number:
  nn:20035809
• Citation:
  Cancer Causes Control 2009 Aug; 20(6):917-923
• Contact Point Address:
  David B. Richardson, University of North Carolina at Chapel Hill, School of Public Health, Department of Epidemiology, CB 7435, Chapel Hill, NC 27599
• Email:
  david.richardson@unc.edu
• CAS Registry Number:
  Asbestos (CAS RN 1332-21-4)
• Federal Fiscal Year:
  2009
• Performing Organization:
  University of North Carolina, Chapel Hill
• Peer Reviewed:
  True
• Start Date:
  20060701
• Source Full Name:
  Cancer Causes and Control
• End Date:
  20090630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:2ba9e9b283009a039d073263e37a71bee9122ab07f15b22715023b4f9a7edee6d2b02d0ef5340191160fa00308d035e8e8dc0e3cc000c7e0721bb4631491aa8d
• Download URL:
  https://stacks.cdc.gov/view/cdc/187527/cdc_187527_DS1.pdf
• File Type:
  [PDF - 258.43 KB ]